Gemara:


Ein Ayah: [From the previous piece - Yannai thought that he could get away with killing out the Rabbis, because in his eyes it was enough that he had a desire to serve Hashem, and he did not think that the details as to how this was supposed to be performed made much difference.]
The lack of knowledge about how to be exact in keeping the Torah and mitzvot comes from a lack of understanding of the importance of Torah within life. The masses can mistakenly think that the foundation of life is eating, drinking, and enjoyment. They may realize that there is a need for an element of service of Hashem, but they may not realize that it is necessary to figure out the details with which this is to be done. With that mindset, one is likely not to value and honor the Torah.
The truth is that only with Torah will we find true life, and the Torah should be connected to all elements of life. After all, the laws of the perfect Torah are laws of living, which "a person will do and live through them" (Vayikra 18:5). Therefore, there is no limit to the honor that the Torah deserves, because all the honor of true life stems from it.
Yannai thought that service of Hashem is just one necessary, but isolated, element of life. Based on this appraisal, he did not believe that it compared to the honor due to the kingdom, which encompasses all the needs of the nation. Shimon ben Shetach came to correct him, informing him that the Torah is the foundation of life. He also sent him the message that the Torah is not to be separated from life to the extent that the one who leads Birkat Hamazon should make a blessing to Hashem who gave food to Yannai and his friends as opposed to the one making the blessing. That would imply that the one who is doing the service of Hashem is disjoint from the life (in this case, eating) that the Torah actually should be connected to. Yannai also mistakenly thought that Shimon should be grateful to him for allowing him to incorporate his dispensable service of Hashem within the royal meal. Shimon ben Shetach told him that the honor comes from the Torah, which elevates the person who is involved in it, as it places all elements of life into their proper order, which then brings real honor to a person. Therefore, Torah should not be separate but intertwined with the ways of life. That is why Shimon ben Shetach was careful to drink first, thereby showing the necessity of connecting the Torah to life and elevating life before making the blessing.